Stainless hlau qhuav khoom, tsis txhob totaub ntxiv lawm 201, 202, 301, 302, 304
Stainless hlau yog lub ntsiab lus ntawm stainless acid-resistant steel. Cov hlau uas tsis muaj zog corrosive xov xwm xws li huab cua, chav, thiab dej los yog stainless yog hu ua stainless hlau; thiab cov hlau uas tiv taus cov tshuaj corrosive media (acid, alkali, ntsev, thiab lwm yam) Cov hlau uas corrodes yog hu ua acid-resistant steel.
Hauv kev siv cov tswv yim, cov hlau uas tiv taus corrosion los ntawm cov xov xwm tsis muaj zog corrosive feem ntau hu ua stainless hlau, thaum hlau uas tiv taus corrosion los ntawm cov tshuaj lom neeg yog hu ua acid-resistant steel. Vim qhov sib txawv ntawm cov tshuaj muaj pes tsawg leeg ntawm ob, cov qub tsis tas yuav tiv taus corrosion los ntawm cov tshuaj lom neeg, thaum tom kawg yog feem ntau stainless. Kev tiv thaiv corrosion ntawm stainless hlau nyob ntawm cov alloying ntsiab muaj nyob rau hauv cov hlau.
Cov qeb:
Feem ntau muab faib ua: raws li metallographic qauv:
Austenitic stainless hlau, ferritic stainless hlau, martensitic stainless hlau.
Raws li peb qhov yooj yim metallographic qauv, duplex steels, nag lossis daus hardening stainless hlau thiab siab alloy steels nrog cov ntsiab lus hlau tsawg dua 50% yog muab los rau cov kev xav tau tshwj xeeb thiab lub hom phiaj.
1. Austenitic stainless hlau.
Lub matrix feem ntau yog austenite qauv (CY theem) nrog lub ntsej muag-centered cubic crystal qauv. Nws tsis yog-sib nqus thiab feem ntau ntxiv dag zog los ntawm kev ua haujlwm txias (thiab tej zaum yuav ua rau qee yam hlau nplaum). Tsim los ntawm American Iron thiab Steel Institute nrog cov lej hauv 200 thiab 300 series, xws li 304.
2. Ferritic stainless hlau.
Lub matrix feem ntau yog ua los ntawm ferrite qauv (ib theem) nrog lub cev-centered cubic crystal qauv. Nws yog hlau nplaum thiab feem ntau tsis tuaj yeem hardened los ntawm kev kho cua sov, tab sis kev ua haujlwm txias tuaj yeem ua rau nws muaj zog me ntsis. Tsim los ntawm American Iron thiab Steel Institute li 430 thiab 446.
3. Martensitic stainless hlau.
Lub matrix yog cov qauv martensite (lub cev-centered cubic lossis cubic), uas yog sib nqus thiab nws cov khoom siv kho tshuab tuaj yeem hloov kho los ntawm kev kho cua sov. Lub koom haum American Iron thiab Steel tus lej 410, 420 thiab 440. Martensite muaj cov qauv austenite ntawm qhov kub thiab txias. Thaum txias rau chav sov ntawm tus nqi tsim nyog, cov qauv austenite tuaj yeem hloov mus rau hauv martensite (uas yog, hardened).
4. Austenitic-ferritic (duplex) stainless hlau.
Lub matrix muaj ob qho tib si austenite thiab ferrite ob-theem qauv, ntawm cov ntsiab lus ntawm cov theem me me matrix feem ntau ntau dua 15%. Nws yog cov hlau tsis muaj hlau uas sib nqus thiab tuaj yeem ua kom muaj zog los ntawm kev ua haujlwm txias. 329 yog ib hom duplex stainless hlau. Piv nrog rau austenitic stainless hlau, duplex steel muaj lub zog siab, thiab nws tsis kam mus rau intergranular corrosion, chloride kev nyuaj siab corrosion thiab pitting corrosion yog ho txhim kho.
5. Cov nag lossis daus hardened stainless hlau.
Stainless hlau uas nws cov matrix yog austenite los yog martensite thiab tuaj yeem hardened los ntawm nag lossis daus hardening. Tsim los ntawm American Iron thiab Steel Institute nrog 600 series tooj, xws li 630, uas yog 17-4PH.
Feem ntau hais lus, ntxiv rau cov alloys, austenitic stainless hlau muaj zoo heev corrosion kuj. Nyob rau hauv ib puag ncig corrosive tsawg, ferritic stainless hlau tuaj yeem siv tau. Nyob rau hauv ib puag ncig corrosive me ntsis, yog tias cov khoom yuav tsum muaj siab Rau lub zog los yog siab hardness, martensitic stainless hlau thiab nag lossis daus hardened stainless hlau yuav siv tau.
